# word = "Python"
# word[0] = 'p'   # 字符串不可被修改

# 字符串的修改
sentence = "Life is short,you need something."
print(sentence[:23] + "Python.")    # 取句子的0-22个字符

# 字符串拼接
print("Python is" + 3 * " good")    # 加号拼接字符串
print("Python is" " good")          # 相邻字符串自然拼接

